Abstract

We demonstrate an approach for background-free three-dimensional imaging of director fields in liquid crystals using stimulated Raman scattering microscopy. This imaging technique is implemented using a single femtosecond pulsed laser and a photonic crystal fiber, providing Stokes and pump frequencies needed to access Raman shifts of different chemical bonds of molecules and allowing for chemically selective and broadband imaging of both pristine liquid crystals and composite materials. Using examples of model three-dimensional structures of director fields, we show that the described technique is a powerful tool for mapping of long-range molecular orientation patterns in soft matter via polarized chemical-selective imaging.

Figures (4)

Principles and a schematic diagram of the SRS-PM setup. (a) Energy diagram of SRS and detection of SRL as the amplitude-modulated component of the pump beam that appears due to the modulated Stokes beam. (b) A schematic diagram of SRS-PM setup integrated with transmission-mode imaging and CARS-PM.